$1.(25$ pts$.)$ What is the output of the following Arduino code? Explain. int led $=9$; int b $=0$; int f $=5$; void setup$()\{$ pinMode$($led$,$ OUTPUT$)$; $\}$ void loop$()\{$ analogWrite$($led$,$ b$)$; b $=$ b $+$ f; if $($b $<=0||$ b $>=255)\{$ f $=-$f; $\}$ delay$(30)$; $\}2.(25$ pts$.)$ Write an Arduino code that counts the number of times a push button connected to pin $3$ is pressed within a $10-$second interval and prints the result to the serial monitor $($Code only$).$